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Photos by Dr. Edward Kohut, all rights reserved, used by permission, 2009
Many times people think that volcanic eruptions affect the economy through the destruction inflicted upon the landscape during an eruption: lahars and pyroclastic flows destroying bridges and homes, ash ruining crops and water, lava flows overunning communities. However, in Hawai’i, a new effect of volcanism has been seen in the agriculture of the state. The volcanic fog – or “vog” as its called – has been causing major problems with farms on the Big Island of Hawai’i. Since the new activity at Halemaumau (see above) began last year, Kilaeua has been spewing much larger volumes (2-4 times more) of volcanic gases such as sulfur dioxide, carbon dioxide, water and carbon monoxide than in previous years. These gases form a brown fog that is caustic to most animals and plants. The sulfur dioxide, in particular, has caused many crops to fail thanks to the production of sulfuric acid with the sulfur dioxide interacts with water – think of it as a very concentrated version of “acid rain” that is seen in the eastern United States.
The solution to this would either be to build “vog-proof” air-filtering greenhouses or planting a limited set of plants that seem to withstand the effects of the vog. Alternately, one can hope that the gas emissions from Kilaeau will return to lower levels, allowing for the plants to survive. In any of these cases, the growers on the island face a large financial hardship in order to keep their businesses alive in the face of the volcano. This passive destruction of plants by Kilaeua shows how even when a volcano seems to be benign, it can inflict millions of dollars of damage on the local economy.

AVO has officially downgraded the status at Redoubt from “Watch” (orange) to “Advisory” (yellow). The seismicity at the volcano has dropped off for the last couple weeks and signs that an eruption was imminent have waned. This, again, shows the difficulty in trying to predict the behavior of a volcano. All the signs were there at Redoubt – increased seismicity, increased heat flow at the summit (seen as melting ice and increased fumarolic output), increased volcanic gases (CO2 and SO2) – but as of right now, it seems like these signs only pointed to magma moving up the system, but not out of the system (i.e., eruption). Anchorage might call this a “near miss,” but Redoubt will erupt again, more likely sooner rather than later. As AVO puts in in their statement today:

It remains possible for unrest at the volcano to change rapidly, advancing from relatively low levels to eruption in time periods as short as 24 hours or less.

And that is why we need volcano monitoring, especially when volcanoes are so complex.

Lava issuing from the current eruptions at Kilauea have started a third ocean entry (and the second within the Hawai’i Volcanoes National Park). The entry is not as dramatic as some, forming a slow, dripping entry of lava into the ocean (see linked video footage), but every little drip adds a little more land to the big island of Hawai’i.
In some other Hawaiian volcano news, the USGS have also posted a video showing the filling and draining of the lava lake in Halemaumau that started last year. Usually, the crater was surrounded by steam and fumes from the degassing magma, but the thermal camera pierced the veil to show the lava rising and falling within the crater.

One of the more impressive areas I visited while in New Zealand was the Waimangu Valley near Mt. Tarawera (above). The valley itself was created by blast explosions (phreatic explosions) during the 1886 eruption of Mt. Tarawera. These eruptions cut right down the axis of the rhyolite domes (most of which erupted ~1305 A.D.) and extended off the volcanic edifice to form the valley to the west of the volcano. In the valley, no juvenile lava was erupted, instead explosions carved out large pits that formed the Waimangu Valley and today the valley is filled with lakes and thermal features (below).
The 1886 eruption at Tarawera was not large by any means, erupting only ~0.7 cubic kilometers of basalt (compare that with the 1305 Kaharoa Rhyolite from Tarawera that erupted 5 cubic kilometers). However, hundreds of Maori villagers died during the eruption and basaltic tephra can be found all over the area north of Tarawera into the Bay of Plenty. Yet, only about a century later, most of the destruction caused by the eruption has been erased by vegetation. Compare the photo of the valley just after the eruption (top) to the one I took in January of 2009 (bottom) to see how things have recovered.Waimangu Valley, 1886Waimangu Valley, 2009
Volcanoes are truly destructive, but still just a flash in the pan for most earth processes.

Yellowstone looks to be keeping everyone on their toes as we ring in 2009. The earthquake swarm reported earlier this week is continuing, with multiple events between 2-3.5 on the Richter Scale. Again, the folks monitoring the caldera – this time the Univ. of Utah – play down these events as normal for any active caldera system … and they’re very likely right. However, the media love to bring up the “supervolcano” angle and we’re even getting expert opinion from (wait for it) Garrison Keillor!. The earthquakes are just normal earthquakes so far – none of the dreaded/anticipated harmonic tremor that might indicate an eruption. This will likely mean that more gas and water monitoring will be occurring in the park in the coming weeks/months.

Some more information is coming out about the activity at Koryak (aka Koryaksky) in Kamchatka. Russian geologist Alexei Ozerov says that the activity at Koryak (note: the image in the article linked here appears to have nothing to do with Koryak) has started with more power than the last known eruption of the volcano in 1956. He also mentions that the volcano is already a danger to aviation in the area (as the closing of the Petropavlosvk-Kamchatsky Airport suggested).
We also have some great images of the volcano, showing the vent on the side of the volcano (see above). It is hard to tell from the images whether juvenile magma is being erupted, or we’re seeing phreatomagmatic explosions caused by the interaction of heat and water (from the melting snow). However, it seems that the increased activity is centered around a previously identified hydrothermal vent on the side of the volcano as some of the images show steam being emitted in November and before – although much weaker than the current rate.{Thanks to reader Thomas Donlon for finding these images of the activity.}

Redoubt Volcano, in Alaska, is one of the more troublesome volcanoes in the state. Not only is it relatively close to population centers, but it also lies directly within the aircraft corridors above the Aleutians for planes headed to Asia and beyond. This means that USGS and AVO geologists have to be especially vigilant in watching Redoubt’s every move.
Currently, the volcano has been recently changed to a yellow (elevated) alert, due to increased steam/volcanic gas emissions (remember, the number one volcanic gas is water vapor) at the volcano. So far, there haven’t been any reported eruptions of ash (i.e., juvenile, fresh magmatic material), but you never know how far behind rumblings and steam that could be (well, you can have an idea that it could be “not far”). It has been almost 19 years since the last eruption (see the famous image of the eruption column above) of Redoubt, so we’re all on pins-and-needles to see whether this activity will lead to a new eruptive period.